6 | Baker Hughes
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5. Install the Seat Ring Gasket (B103) in seat ring gasket
groove.
6.
Install the Body Gasket (B015) in the gasket groove in the
Valve Body (B001).
7.
Place the Venturi (B142) on the underside of the seat ring
face and align it with the seat ring opening so that the Lower
Flange (B010) can be lowered in place.
8.
Lubricate the exposed Body Stud (B002) threads using
Gripcott NF or equivalent.
9.
Lower the Lower Flange (B010) over the Venturi (B142) and
then onto the locating boss of the Valve Body (B001).
Body Stud and Nut Torquing
1.
Lubricate the Body Nut (B014) contact surfaces using
Gripcott NF or equivalent.
2.
Install the Body Nuts (B014) onto the Body Studs (B002).
Prior to and while tightening the Body Nuts (B014), ensure
that the Lower Flange (B010) and valve trim are centered
and free moving.
Single bolt circle arrangement
1.
Tighten the Body Nuts (B014) in the sequence indicated by
the Figure 1 or 2 or 3 based on quantity, and torque them
in successive, uniform, and progressive levels using a
calibrated torque wrench. During torquing, ensure that the
Lower Flange (B010) face stays parallel to the Valve Body
(B001) face. Torque to the maximum values in Table 1 for
ASME Class 2500 or Table 2 for ASME Class 600. When
the final torque values are achieved, confirm that the Lower
Flange (B010) face is contacting the Valve Body (B001)
face.
Double bolt circle arrangement
1.
Begin with the internal bolt pattern and torque the nuts
in the order indicated by the Figure 4 or 5 depending on
bolt quantity, and torque them in successive, uniform and
progressive levels using a calibrated torque wrench. When
the torque values in Table 1 are reached, confirm that the
Lower Flange (B010) face is in metal to metal contact with
the Valve Body (B001) face.
2.
Follow with the external bolt pattern and torque the nuts in
the order indicated by the Figure 4 or 5 depending on bolt
quantity, and torque them in successive, uniform and
progressive levels. When the torque values in Table 1 are
reached, confirm that the Lower Flange (B010) face is in
metal to metal contact with the Valve Body (B001) face.
The valve should now be inverted again to a
right-side-up position to assemble the packing
box and install the actuator. Inverting the valve
requires pre-planning of the rigging and lifting
process. Once inverted, the valve must be cradled
in an appropriate fixture to support its weight and
provide stability during maintenance activities.
Plug/Stem S/A
The Plug/Stem sub-assembly (B119) are assembled under tight
tolerances to prevent damage to the hardened (and extremely
brittle) parts. For this reason, the Plug/Stem sub-assembly (B119)
must always be replaced together as a complete assembly with
factory OEM parts.
Seat Ring S/A and Venturi S/A
Note: These sub-assemblies are each fit together using a
heat shrinking process. The seat and liner of each of these
assemblies should never be separated. The assemblies
must always be replaced as complete assemblies using
factory OEM parts.
Valve Reassembly
Make sure the valve body and gasket surfaces are clean and
free of any damage.
The 74000 Series must always be reassembled with new packing
and gaskets. Before disassembly, make sure the recommended
spare parts are available for reassembly.
Body Stud Assembly
Lubricate threads of the Body Studs (B002), using Gripcott NF or
equivalent, and screw them into the Valve Body (B001) until the
studs bottom out. Do not over torque as it will damage the stud
and prevent future removal.
Bull Nose Guide
Bull Nose Trim requires a Bull Nose Guide (B011) which is
welded into the Valve Body (B001). This guide is installed at
the factory and should not require field service. If the Bull Nose
Guide (B011) has need for replacement, contact Baker Hughes
Masoneilan Engineering for guidance regarding removal and re-
installation.
Trim / Lower Flange
1.
Install the Plug/Stem sub-assembly (B120/B112) into the
Valve Body (B001), leading with the stem side.
2.
For trim sizes 2” and less, install the Upper Seat Ring Gasket
(B103a) in the gasket groove in the Valve Body (B001).
3. For trim sizes greater than 2”, install the Conical Spring
(B013) in the Valve Body (B001). Make sure spring is
correctly installed per Figure 6, where the spring OD is in
contact with the valve body face.
4.
Install the Seat Ring (B102) in the Valve Body (B001), sliding
it onto the Plug/Stem sub-assembly (B112).
The 74000 Series valve is a bottom entry design
and thus the valve must be inverted for proper
reassembly. Inverting the valve requires pre-
planning of the rigging and lifting process.
Once inverted, the valve must be cradled in an
appropriate fixture to support its weight and
provide stability during maintenance activities.
